How to discover asteroid impacts

Congratulations to the discoverer, but I’m a little disappointed that the article wasn’t about what I was expecting it to be about, which was a tool for visually emphasizing the circular features of Google Earth images. Instead, the author just saw them in unmassaged Google Earth colours!

It reminds me that a couple of months ago a friend directed me to Google Earth and I got fascinated by the swirly coloured features of the Sahara desert’s interior. I thought at first it must be some false colour emphasis to bring out subtle features of the desert, but apparently not, those are just normal colour changes.

I grew up with maps that showed deserts as uniform yellow solitudes with no interesting structure, in contrast with the inhabited regions and their many and varied shades. I hadn’t appreciated that that was nothing more than an expression on the map of where the mapmakers’ focus of attention was: nobody was making maps for Bedouins, or if they were, I wasn’t seeing them.

I emailed my friend back with my discovery, and a few lines of Lewis Carroll:

He had bought a large map representing the sea,
Without the least vestige of land:
And the crew were much pleased when they found it to be
A map they could all understand.

“What’s the good of Mercator’s North Poles and Equators,
Tropics, Zones, and Meridian Lines?”
So the Bellman would cry: and the crew would reply
“They are merely conventional signs!

“Other maps are such shapes, with their islands and capes!
But we’ve got our brave Captain to thank:
(So the crew would protest) “that he’s bought us the best –
A perfect and absolute blank!”